The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Fluid lines used in vehicle fuel and coolant systems have to withstand extreme temperature and pressures, without loss of the fluid being conveyed.
It is well known to use a variety of materials to construct the hoses employed in such systems as well as the development of joints to connect the hoses to different components.
U.K. Patent Application No. 2 257 764 describes a fluid tight sealing ring A shown in FIG. 1. It is used for fitting a flexible hose 1 to a rigid tubular element 2. The ring A has an internal hooked projection 7 and an internal clamping projection 8 which are axially spaced apart. The clamping projection 8 of the ring A has an inner diameter which is preferably slightly less than or equal to the outer diameter of the flexible hose 1. The inner diameter of the hooked projection 7 is preferably greater than the nominal outer diameter of said hose. The ring can thus be easily positioned on the end of the hose before it is force fitted on to the rigid tubular element 2. Once the ring A has been positioned onto the hose, the end of the latter is force fitted onto the rigid tubular element 2, and then the ring A is forcedly slid over the hose 1 towards the retaining projection 4 of the rigid tubular element. In order to provide fluid tight connection, a mechanical tool is required. The hooked projection 7 of the ring A has a lead surface 7a which faces outwardly, its profile being inclined like the profile of the surface 4a of the retaining projection 4 of the tubular element 2. The inner diameter of the projection 7 of the ring A is less than the outer diameter of the retaining projection 4 of the rigid tubular element. When the ring A is forcedly slid over the hose 1 fitted onto the rigid tubular element 2, the frusto-conical lead-in surface 7a of the hooked projection first contacts the surface 4a of the retaining projection of the union. As the ring A is thrust further in the direction of the projection 4 of the union, that portion of the ring A formed with the hooked projection 7 deflects elastically so as to ride over the retaining projection 4 of the union to reach the hooked position. Once it has passed this projection, the resilient contraction of that portion of the ring A which had previously deflected forms an almost irreversible engagement of the ring A with the projection 4 of the rigid tubular element 2.
U.S. Pat. No. 6,641,177 for example describes a coupling system for coupling flexible tubing between ports which includes a port element provided with a sharp barb, and a clamp which secures the tubing over the port element. The clamp is forcibly slid along the tubing such that the barbs ride over and then lock about the barb of the port element.
Korean Patent No. KR 101177674 discloses a tube connection structure for connecting an in/outlet, or other accessories of a filter to a purified water line of a water purifier or refrigerator. The tube connection structure comprises tubing and fastening cap which are assembled by forced fit. The fastening cap is equipped with cylindrical metallic reinforcement to reinforce the fitting.
The drawback of these various known coupling systems is that is very hard to assemble manually the coupling system in order to provide a fluid-tight seal. Of course, it is also difficult to disconnect the system without using a tool.